…why would cookies ever need to work across domains? Authentication, shopping carts and all that good stuff can happen on the same domain. Third-party cookies, on the other hand,
seem custom made for tracking and frankly, not much else.
…
Then there’s third-party JavaScript.
In retrospect, it seems unbelievable that third-party JavaScript is even possible. I mean, putting arbitrary code—that can then inject
even more arbitrary code—onto your website? That seems like a security nightmare!
I imagine if JavaScript were being specced today, it would almost certainly be restricted to the same origin by default.
…
Jeremy hits the nail on the head with third-party cookies and Javascript: if the Web were invented today, there’s no way that these potentially privacy and security-undermining features
would be on by default, globally. I’m not sure that they’d be universally blocked at the browser level as Jeremy suggests, though: the Web has always been about empowering developers,
acting as a playground for experimentation, and third-party stuff does provide benefits: sharing a login across multiple subdomains, for example (which in turn can exist as a
security feature, if different authors get permission to add content to those subdomains).
Instead, then, I imagine that a Web re-invented today would treat third-party content a little like we treat CORS or we’re
beginning to treat resource types specified by Content-Security-Policy and Feature-Policy headers. That is, website owners would need to “opt-in” to which third-party domains could be
trusted to provide content, perhaps subdivided into scripts and cookies. This wouldn’t prohibit trackers, but it would make their use less of an assumed-default (develolpers would have
to truly think about the implications of what they were enabling) and more transparent: it’d be very easy for a browser to list (and optionally block, sandbox, or anonymise) third-party
trackers could potentially target them, on a given site, without having to first evaluate any scripts and their sources.
I was recently inspired by Dave Rupert to remove
Google Analytics from this blog. For a while, there’ll have been no third-party scripts being delivered on this site at all, except through iframes (for video embedding etc., which
is different anyway because there’s significantly less scope leak). Recently, I’ve been experimenting with Jetpack because I get it for free through
my new employer, but I’m always looking for ways to improve how well my site “stands alone”: you can block all third-party resources
and this site should still work just fine (I wonder if I can add a feature to my service worker to allow visitors to control exactly what third party content they’re exposed to?).
That moment when you realise, to your immense surprise, that the research you’ve spent most of the year on might actually demonstrate the thing you set out to test after all. 😲
Screw you, null hypothesis.
This is part of a series of posts on computer terminology whose popular meaning – determined by surveying my friends – has significantly
diverged from its original/technical one. Read more evolving words…
A few hundred years ago, the words “awesome” and “awful” were synonyms. From their roots, you can see why: they mean “tending to or causing awe” and “full or or characterised by awe”,
respectively. Nowadays, though, they’re opposites, and it’s pretty awesome to see how our language continues to evolve. You know what’s awful, though? Computer viruses. Right?
“Oh no! A virus has stolen all my selfies and uploaded them to a stock photos site!”
You know what I mean by a virus, right? A malicious computer program bent on causing destruction, spying on your online activity, encrypting your files and ransoming them back to you,
showing you unwanted ads, etc… but hang on: that’s not right at all…
Virus
What people think it means
Malicious or unwanted computer software designed to cause trouble/commit crimes.
What it originally meant
Computer software that hides its code inside programs and, when they’re run, copies itself into other programs.
The Past
Only a hundred and thirty years ago it was still widely believed that “bad air” was the principal cause of disease. The idea that tiny germs could be the cause of infection was only
just beginning to take hold. It was in this environment that the excellent scientist Ernest Hankin travelled around
India studying outbreaks of disease and promoting germ theory by demonstrating that boiling water prevented cholera by killing the (newly-discovered) vibrio cholerae bacterium.
But his most-important discovery was that water from a certain part of the Ganges seemed to be naturally inviable as a home for vibrio cholerae… and that boiling this
water removed this superpower, allowing the special water to begin to once again culture the bacterium.
Hankin correctly theorised that there was something in that water that preyed upon vibrio cholerae; something too small to see with a microscope. In doing so, he was probably
the first person to identify what we now call a bacteriophage: the most common kind of virus. Bacteriophages were briefly seen as exciting for their medical potential. But then
in the 1940s antibiotics, which were seen as far more-convenient, began to be manufactured in bulk, and we stopped seriously looking at “phage therapy” (interestingly, phages are seeing a bit of a resurgence as antibiotic resistance becomes increasingly problematic).
It took until the development of the scanning electron microscope in the mid-20th century before we’d actually “see” a virus.
But the important discovery kicked-off by the early observations of Hankin and others was that viruses exist. Later, researchers would discover how these viruses
work1:
they inject their genetic material into cells, and this injected “code” supplants the unfortunate cell’s usual processes. The cell is “reprogrammed” – sometimes after a dormant
period – to churns out more of the virus, becoming a “virus factory”.
Let’s switch to computer science. Legendary mathematician John von Neumann, fresh from showing off his expertise in
calculating how shaped charges should be used to build the first atomic bombs, invented the new field of cellular autonoma. Cellular autonoma are computationally-logical,
independent entities that exhibit complex behaviour through their interactions, but if you’ve come across them before now it’s probably because you played Conway’s Game of Life, which made the concept popular decades after their invention. Von Neumann was very interested
in how ideas from biology could be applied to computer science, and is credited with being the first person to come up with the idea of a self-replicating computer program which would
write-out its own instructions to other parts of memory to be executed later: the concept of the first computer virus.
This is a glider factory… factory. I remember the first time I saw this pattern, in the 1980s, and it sank in for me that cellular autonoma must logically be capable of any
arbitrary level of complexity. I never built a factory-factory-factory, but I’ll bet that others have.
Retroactively-written lists of early computer viruses often identify 1971’s Creeper as the first computer virus:
it was a program which, when run, moved (later copied) itself to another computer on the network and showed the message “I’m the creeper: catch me if you can”. It was swiftly followed
by a similar program, Reaper, which replicated in a similar way but instead of displaying a message attempted to
delete any copies of Creeper that it found. However, Creeper and Reaper weren’t described as viruses at the time and would be more-accurately termed
worms nowadays: self-replicating network programs that don’t inject their code into other programs. An interesting thing to note about them, though, is that – contrary
to popular conception of a “virus” – neither intended to cause any harm: Creeper‘s entire payload was a relatively-harmless message, and Reaper actually tried to do
good by removing presumed-unwanted software.
Another early example that appears in so-called “virus timelines” came in 1975. ANIMAL presented as a twenty
questions-style guessing game. But while the user played it would try to copy itself into another user’s directory, spreading itself (we didn’t really do directory permissions back
then). Again, this wasn’t really a “virus” but would be better termed a trojan: a program which pretends to be something that it’s not.
“Malware? Me? No siree… nothing here but this big executable horse.”
It took until 1983 before Fred Cooper gave us a modern definition of a computer virus, one which – ignoring usage by laypeople –
stands to this day:
A program which can ‘infect’ other programs by modifying them to include a possibly evolved copy of itself… every program that gets infected may also act as a virus and thus the
infection grows.
This definition helps distinguish between merely self-replicating programs like those seen before and a new, theoretical class of programs that would modify host programs such
that – typically in addition to the host programs’ normal behaviour – further programs would be similarly modified. Not content with leaving this as a theoretical, Cooper wrote the
first “true” computer virus to demonstrate his work (it was never released into the wild): he also managed to prove that there can be no such thing as perfect virus detection.
(Quick side-note: I’m sure we’re all on the same page about the evolution of language here, but for the love of god don’t say viri. Certainly don’t say virii.
The correct plural is clearly viruses. The Latin root virus is a mass noun and so has no plural, unlike e.g.
fungus/fungi, and so its adoption into a count-noun in English represents the creation of a new word which should therefore, without a precedent to the
contrary, favour English pluralisation rules. A parallel would be bonus, which shares virus‘s linguistic path, word ending, and countability-in-Latin: you wouldn’t say
“there were end-of-year boni for everybody in my department”, would you? No. So don’t say viri either.)
No, no, no, no, no. The only wholly-accurate part of this definition is the word “program”.
Viruses came into their own as computers became standardised and commonplace and as communication between them (either by removable media or network/dial-up connections) and Cooper’s
theoretical concepts became very much real. In 1986, The Virdim method brought infectious viruses to the DOS platform, opening up virus writers’ access to much of the rapidly growing business and home computer markets.
The Virdim method has two parts: (a) appending the viral code to the end of the program to be infected, and (b) injecting early into the program a call to the appended code. This
exploits the typical layout of most DOS executable files and ensures that the viral code is run first, as an infected program
loads, and the virus can spread rapidly through a system. The appearance of this method at a time when hard drives were uncommon and so many programs would be run from floppy disks
(which could be easily passed around between users) enabled this kind of virus to spread rapidly.
For the most part, early viruses were not malicious. They usually only caused harm as a side-effect (as we’ve already seen, some – like Reaper – were intended to be not just
benign but benevolent). For example, programs might run slower if they’re also busy adding viral code to other programs, or a badly-implemented virus might
even cause software to crash. But it didn’t take long before viruses started to be used for malicious purposes – pranks, adware, spyware, data ransom, etc. – as well as to carry
political messages or to conduct cyberwarfare.
XKCD already explained all of this in far fewer words and a diagram.
The Future
Nowadays, though, viruses are becoming less-common. Wait, what?
Yup, you heard me right: new viruses aren’t being produced at remotely the same kind of rate as they were even in the 1990s. And it’s not that they’re easier for security software to
catch and quarantine; if anything, they’re less-detectable as more and more different types of file are nominally “executable” on a typical computer, and widespread access to
powerful cryptography has made it easier than ever for a virus to hide itself in the increasingly-sprawling binaries that litter modern computers.
Soo… I click this and all the viruses go away, right? Why didn’t we do this sooner?
The single biggest reason that virus writing is on the decline is, in my opinion, that writing something as complex as a a virus is longer a necessary step to illicitly getting your
program onto other people’s computers2!
Nowadays, it’s far easier to write a trojan (e.g. a fake Flash update, dodgy spam attachment, browser toolbar, or a viral free game) and trick people into running it… or else to write a
worm that exploits some weakness in an open network interface. Or, in a recent twist, to just add your code to a popular library and let overworked software engineers include it in
their projects for you. Modern operating systems make it easy to have your malware run every time they boot and it’ll quickly get lost amongst the noise of all the
other (hopefully-legitimate) programs running alongside it.
In short: there’s simply no need to have your code hide itself inside somebody else’s compiled program any more. Users will run your software anyway, and you often don’t even
have to work very hard to trick them into doing so.
Verdict: Let’s promote use of the word “malware” instead of “virus” for popular use. It’s more technically-accurate in the vast majority of cases, and it’s actually a
more-useful term too.
Footnotes
1 Actually, not all viruses work this way. (Biological) viruses are, it turns out, really
really complicated and we’re only just beginning to understand them. Computer viruses, though, we’ve got a solid understanding of.
2 There are other reasons, such as the increase in use of cryptographically-signed
binaries, protected memory space/”execute bits”, and so on, but the trend away from traditional viruses and towards trojans for delivery of malicious payloads began long before these
features became commonplace.
I’ve just cleared out my desk at the Bodleian in anticipation of my imminent departure and discovered that I’ve managed to
successfully keep not only my P60s but also every payslip I’ve ever received in the 8½ years I’ve worked there. At a stretch, I
might just end up requiring those for the current tax year but I can’t conceive of any reason I’ll ever need the preceding hundred or so of them, so the five year-old and I
shredded them all.
If you’ve ever wanted to watch five solid minutes of cross-cut shredding shot from an awkwardly placed mobile phone camera, this is the video for you. Everybody else can move along.
Can we solve [the problem of supply-chain attacks] by building trustworthy systems out of untrustworthy parts?
It sounds ridiculous on its face, but the Internet itself was a solution to a similar problem: a reliable network built out of unreliable parts. This was the result of decades of
research. That research continues today, and it’s how we can have highly resilient distributed systems like Google’s network even though none of the individual components are
particularly good. It’s also the philosophy behind much of the cybersecurity industry today: systems watching one another, looking for vulnerabilities and signs of attack.
Security is a lot harder than reliability. We don’t even really know how to build secure systems out of secure parts, let alone out of parts and processes that we can’t trust and
that are almost certainly being subverted by governments and criminals around the world. Current security technologies are nowhere near good enough, though, to defend against these
increasingly sophisticated attacks. So while this is an important part of the solution, and something we need to focus research on, it’s not going to solve our near-term problems.
…
Schneier provides a great summary of the state of play with nation-state supply-chain attacks, using the Huawei 5G controversy as a jumping-off point but with reference to the fact that
China are far from the only country that weaken the security and privacy of the world’s citizens in order to gain an international spying advantage. He goes on to explain what
he sees as the two broad schools of thought are in providing technical solutions to this class of problems, and demonstrates that both are for the time being beyond our reach. The
excerpt above comes from his examination of the second school of thought, and it’s a pretty-compelling illustration of why this is a different class of problem that the ones we’ve used
to build a reliable Internet.
Let’s face the truth. We are in an abusive relationship with our phones.
Ask yourself the first three questions that UK non-profit Women’s Aid
suggests to determine if you’re in an abusive relationship:
Has your partner tried to keep you from seeing your friends or family?
Has your partner prevented you or made it hard for you to continue or start studying, or from going to work?
Does your partner constantly check up on you or follow you?
If you substitute ‘phone’ for ‘partner’, you could answer yes to each question. And then you’ll probably blame yourself.
…
A fresh take by an excellent article. Bringing a feminist viewpoint to our connection to our smartphones helps to expose the fact that our relationship with the devices would easily be
classified as abusive were they human. The article goes on to attempt to diffuse the inevitable self-blame that comes from this realisation and move forward to propose a more-utopian
future in which our devices might work for us, rather than for the companies that provide the services for which we use them.
But while we’ve learned to distrust user names and text more generally, pictures are different. You can’t synthesize a picture out of nothing, we assume; a picture had to be of
someone. Sure a scammer could appropriate someone else’s picture, but doing so is a risky strategy in a world with google reverse search and so forth. So we tend to trust pictures.
A business profile with a picture obviously belongs to someone. A match on a dating site may turn out to be 10 pounds heavier or 10 years older than when a picture was taken, but if
there’s a picture, the person obviously exists.
No longer. New adverserial machine learning algorithms allow people to rapidly generate synthetic ‘photographs’ of people who have never existed. Already faces of this sort are
being used in espionage.
Computers are good, but your visual processing systems are even better. If you know what to look for, you can spot these fakes at a single glance — at least for the time being. The
hardware and software used to generate them will continue to improve, and it may be only a few years until humans fall behind in the arms race between forgery and detection.
Our aim is to make you aware of the ease with which digital identities can be faked, and to help you spot these fakes at a single glance.
…
I was at a conference last month where research was presented which concluded pretty solidly that the mechanisms used to
make “deepfakes” meant that it was probably impossible to create artificial intelligence that can learn to distinguish between real and fake pictures of humans. Simply put, this is
because the way we make such images is with generative adversarial networks, an AI technique which thrives upon having an effective discriminator component, and any research into differentiating between real and fake images
feeds the capability of the next generation of discriminators!
Instead, then, the best medium-term defence against deepfakes is training humans to be able to identify them, and that’s what this website aims to do. I was pleased that I did
very well on my first attempt (I sort-of knew what to look for already, based on a basic understanding of the underlying technologies) but I was also pleased that I was able to learn to
do better with the aid of the authors’ tips. Nice.
The other day, I saw someone on Twitter say (I’m not linking to the original tweet because I don’t want to pile-on the author):
I don’t bother with frameworks, I just use vanilla JS.
Roughly translated:
I’m smarter than the thousands of people who tried to solve the problems I’m about to solve. I’m an expert on security, a11y, browser support, and perf. I don’t care about ROI, I
just want to code.
Here’s the thing: frameworks don’t really help you with this stuff.
Very much this. People who use Javascript frameworks because they think they protect them from common web development pitfalls are simply trading away a set of known, solvable problems
and taking on a different set of unknown, unsolvable ones.
I’m not anti-framework, but I am pro-informed-developer. If security, accessibility, performance, and browser support are things you care about – and they absolutely should be – then
you need to know the impact that the tools you choose have upon those things. It’s easy to learn the impact that vanilla JS has on them, but
it’s harder to understand exactly what impact a framework might have or how that impact might be affected by interactions between it and all of the other frameworks and
libraries you mix-in. And many developers don’t bother to learn.
Use frameworks if they’re the right tool for your job. But you should work towards understanding your tools. Incidentally: in doing so, you’ll probably come to discover that
frameworks are the right tool for fewer jobs than you thought.
The reality is that your sensitive data has likely already been stolen, multiple times. Cybercriminals have your credit card information. They have your social
security number and your mother’s maiden name. They have your address and phone number. They obtained the data by hacking any one of the hundreds of companies you entrust with the
data — and you have no visibility into those companies’ security practices, and no recourse when they lose your data.
Given this, your best option is to turn your efforts toward trying to make sure that your data isn’t used against you. Enable two-factor authentication for all important
accounts whenever possible. Don’t reuse passwords for anything important — and get a password manager to remember them all.
Israel has acknowledged that its recent airstrikes against Hamas were a
real-time response to an ongoing cyberattack. From Twitter:
CLEARED FOR RELEASE: We thwarted an attempted Hamas cyber offensive against Israeli targets. Following our successful cyber defensive operation, we targeted a building where the
Hamas cyber operatives work.
I expect this sort of thing to happen more — not against major countries, but by larger countries against smaller powers. Cyberattacks are too much of a nation-state equalizer
otherwise.
I doubt that this is actually the first “kinetic” retaliation to a cyber attack; however it’s probably the first one to be openly acknowledged by either of the parties
involves. Schneier’s observation that cyberwarfare is an equaliser is correct and it’s exactly why a savvy nation-state would consider this kind of response… but let’s not forget that
such cyberattacks are only as viable as they are because nation-states favour cyber-offense over cuber-defence in the first place: they’re interested in building 0-day weapons that they
can use against their enemies (and their own citizens) and this entire approach runs counter to the idea of improving defensive security.
From a G7 meeting of interior ministers in Paris this month, an “outcome document“:
Encourage Internet companies to establish lawful access solutions for their products and services, including data that is encrypted, for law enforcement and competent authorities
to access digital evidence, when it is removed or hosted on IT servers located abroad or encrypted, without imposing any particular technology and while ensuring that assistance
requested from internet companies is underpinned by the rule law and due process protection. Some G7 countries highlight the importance of not prohibiting, limiting, or weakening
encryption;
There is a weird belief amongst policy makers that hacking an encryption system’s key management system is fundamentally different than hacking the system’s encryption algorithm.
The difference is only technical; the effect is the same. Both are ways of weakening encryption.
The G7’s proposal to encourage encryption backdoors demonstrates two unsurprising things about the politicians in attendance, including that:
They’re unwilling to attempt to force Internet companies to add backdoors (e.g. via legislation, fines, etc.), making their resolution functionally toothless, and
More-importantly: they continue to fail to understand what encryption is and how it works.
Somehow, then, this outcome document simultaneously manages to both go too-far (for a safe and secure cryptographic landscape for everyday users) and not-far-enough (for law enforcement
agencies that are in favour of backdoors, despite their huge flaws, to actually gain any benefit). Worst of both worlds, then.
Needless to say, I favour not attempting to weaken encryption, because such measures (a) don’t work against foreign powers, terrorist groups, and hardened criminals and (b)
do weaken the personal security of law-abiding citizens and companies (who can then become victims of the former group). “Backdoors”, however phrased, are a terrible idea.
“the local part of my email address is just the letter ‘d’ by itself, which means microsoft has imposed the interesting restriction that my randomly generated password cannot
contain the letter ‘d’”
the local part of my email address is just the letter 'd' by itself, which means microsoft has imposed the interesting restriction that my randomly generated password cannot contain
the letter 'd' pic.twitter.com/tqTklyotTj
@notrevenant@PWtoostrong you wouldn’t believe how often I’m told I’m not allowed to use the
letter “Q” in passwords, because “my password mustn’t contain my surname”. O_o
In a blog post, cryptographer Matthew Green summarized the technical problems
with this GCHQ proposal. Basically, making this backdoor work requires not only changing the cloud computers that oversee communications, but it also means changing the client program
on everyone’s phone and computer. And that change makes all of those systems less secure. Levy and Robinson make a big deal of the fact that their backdoor would only be targeted
against specific individuals and their communications, but it’s still a general backdoor that could be
used against anybody.
The basic problem is that a backdoor is a technical capability — a vulnerability — that is available to anyone who knows about it and has access to it. Surrounding that vulnerability
is a procedural system that tries to limit access to that capability. Computers, especially internet-connected computers, are inherently hackable, limiting the effectiveness of any
procedures. The best defense is to not have the vulnerability at all.
…
Lest we ever forget why security backdoors, however weasely well-worded, are a terrible idea, we’ve got Schneier calling them out. Spooks in democratic nations the
world over keep coming up with “innovative” suggestions like this one from GCHQ but they keep solving the same problem, the technical problem of key distribution or
key weakening or whatever it is that they want to achieve this week, without solving the actual underlying problem which is that any weakness introduced to a secure
system, even a weakness that was created outwardly for the benefit of the “good guys”, can and eventually will be used by the “bad guys” too.
Furthermore: any known weakness introduced into a system for the purpose of helping the “good guys” will result in the distrust of that system by the people they’re trying to
catch. It’s pretty trivial for criminals, foreign agents and terrorists to switch from networks that their enemies have rooted to networks that they (presumably) haven’t, which tends to
mean a drift towards open-source security systems. Ultimately, any backdoor that gets used in a country with transparent judicial processes becomes effectively public
knowledge, and ceases to be useful for the “good guys” any more. Only the non-criminals suffer, in the long run.
An open source checklist of resources designed to improve your online privacy and security. Check things off to keep track as you go.
…
I’m pretty impressed with this resource. It’s a little US-centric and I would have put the suggestions into a different order, but many of the ideas on it are very good and are
presented in a way that makes them accessible to a wide audience.
2004 called, @virginmedia. They asked me to remind you that maximum password lengths and prohibiting pasting makes your security worse, not better. @PWTooStrong
In more detail:
Why would you set an upper limit on security? It can’t be for space/capacity reasons because you’re hashing my password anyway in accordance with best security practice, right?
(Right?)
Why would you exclude spaces, punctuation, and other “special” characters? If you’re afraid of injection attacks, you’re doing escaping wrong (and again: aren’t you hashing
anyway?). Or are you just afraid that one of your users might pick a strong password? Same for the “starts with a letter” limitation.
Composition rules like “doesn’t contain the same character twice in a row” reflects wooly thinking on that part of your IT team: you’re saying for example that “abababab” is
more-secure than “abccefgh”. Consider using exclusion lists/blacklists for known-compromised/common passwords e.g. with HaveIBeenPwned
and/or use entropy-based rather than composition-based rules e.g. with zxcvbn.
Disallowing pasting into password fields does nothing to prevent brute-force/automated attacks but frustrates users who use password managers (by forcing them to retype their
passwords, you may actually be reducing their security as well as increasing the likelihood of mistakes) and can have an impact on accessibility too.
Counterarguments I anticipate: (a) it’s for your security – no it’s not; go read any of the literature from the last decade and a half, (b) it’s necessary for integration with a
legacy system – that doesn’t fill me with confidence: if your legacy system is reducing your security, you need to update or replace your legacy system or else you’re setting yourself
up to be the next Marriott, Equifax, or Friend Finder Network.